Classification of energy storage equipment

Energy storage equipment is mainly divided into the following four categories according to the different technical principles:

Electrochemical energy storage: One of the most common and mature technologies, mainly including batteries and supercapacitors.
Battery: Converts electrical energy into chemical energy through a chemical reaction for storage, and converts it back into electrical output when needed. Common battery types are lead-acid batteries, lithium-ion batteries, sodium-ion batteries, nickel-metal hydride batteries, etc. Lithium-ion batteries, due to their high energy density, long cycle life and environmental friendliness, have become the first choice in electric vehicles, portable electronic devices and renewable energy systems.
Supercapacitors: Devices capable of efficiently storing electrical energy, with high power density and fast charging and discharging characteristics. Although their energy density is relatively low, supercapacitors play an important role in situations where instantaneous high-power output is required, such as power grid peaking and electric vehicle acceleration.
Mechanical energy storage: Storage by converting mechanical energy into other forms of energy, common forms include pumped storage, flywheel storage, and compressed air storage.
Pumped storage: The use of off-peak hours to pump water to higher storage, and then release the water during peak hours to generate electricity. It has the advantages of large capacity, long life and mature technology, but it is limited by terrain conditions and the investment cost is high.
Flywheel energy storage: The use of high-speed rotating flywheel to store mechanical energy, when the need to release energy, through the flywheel to drive the generator to generate electricity. It has the characteristics of high power density and fast response speed, and is suitable for the occasions where the electric energy needs to be adjusted quickly.
Compressed air energy storage: Air is compressed and stored by electricity, and the compressed air is released when needed to drive a turbine to generate electricity. Large-scale energy storage can be achieved, but the efficiency is relatively low and there are certain requirements for station construction conditions.
Thermal energy storage: The use of thermal storage materials or heat pumps to store and release thermal energy, suitable for scenarios that require long-term storage of thermal energy, such as solar thermal power generation, heating systems, etc.
Electromagnetic energy storage: including inductive energy storage and capacitor energy storage, the former through the inductive element to store magnetic energy, the latter through the capacitive element to store electrical energy. It has the advantages of high response speed, low loss and so on, and has important applications in research experiments and magnetic levitation transportation.